OAKLAND (CBS SF) – About 300 people gathered at an auditorium at Oakland police headquarters Wednesday morning to pay tribute to four officers who were killed by a wanted parolee three years ago.

The gathering also served as the official dedication ceremony for a freeway sign honoring the four officers that was installed on an overpass at the Keller Avenue exit along Interstate Highway 580 in Oakland.

Thanks to state legislation, the overpass will be known as the “Sgt. Mark Dunakin, Sgt. Ervin Romans, Sgt. Daniel Sakai and Officer John Hege Memorial Bridge.”

There is already one such sign in place on the overpass facing eastbound traffic; the sign dedicated Wednesday was put up on the westbound side of the highway.

The four officers were shot and killed by parolee Lovelle Mixon on March 21, 2009. Mixon was fatally shot by other officers that day.

Oakland Police Chief Howard Jordan said that day in the department’s history “is our 9/11 and will always be remembered.”

KCBS’ Margie Shafer Reports:

Jordan told those at the ceremony, “As you travel through Oakland, please pay tribute to these heroes.”

He described receiving a call from another top police official three years ago informing him of the killings.

“It’s a phone call I wish I had never received,” Jordan said.

Alameda County District Attorney Nancy O’Malley said the freeway

sign “will remind us forever of the price these officers paid in the line of duty.”

O’Malley said, “We pray that no other police officers have their names engraved on the wall of fallen Oakland police officers, and we hope that this is the last bridge dedicated to fallen officers.”

A short video of family members reflecting on their memories of the four officers was played at the ceremony.

Afterward, family members of the fallen officers signed the back of the freeway sign, which was displayed in the lobby of the police headquarters building.

Earlier Wednesday, the family members placed a wreath at the site of the existing sign.

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